- Preheat your oven to 350°F (175°C). A well-heated oven is crucial; it allows the bread to rise perfectly and ensures even baking. 
- Grease a 9x5 inch loaf pan with butter or spray it with non-stick cooking spray. This step is essential to avoid a sticky situation later on! 
- In a large mixing bowl, mash your 4 ripe bananas until smooth. This is where the irresistible aroma begins. Next, whisk in the melted butter, egg, and Greek yogurt until everything is well combined. 
- In a separate bowl, mix together the gluten-free flour, baking soda, sea salt, and ground cinnamon. This helps distribute the rising agent evenly throughout the batter. 
- Slowly fold the dry mixture into the wet ingredients. Use a spatula to gently combine, taking care not to over-mix. This is a good time to toss in the chopped walnuts. 
- Pour the batter into your prepared loaf pan and smooth out the top. Give the pan a gentle tap on the counter to remove air bubbles. 
- Now, place the loaf pan in the preheated oven. Bake for approximately 60–65 minutes or until a toothpick inserted into the center comes out clean. Your kitchen is about to smell heavenly! 
- Once baked, remove the banana bread from the oven and let it cool in the pan for about 10 minutes. Then, carefully transfer it onto a wire rack to cool completely. Patience is key!